Refrigeration



p i 1940- R. s. TAYLOR 2,195,604

REFRIGERAT I 0N Filed March 27, I 1957 Patented Apr. 2, 1940 UNITED STATES REFRIGERATION Robert S. Taylor, Evansville, Ind., assignor to Serve], Inc., New York, N. Y., a corporation of Delaware Application March 27, 1987, Serial No. 133,449

3 Claims.

This invention relates to the art ofrefrigeration and more particularly to a refrigeration process and a refrigeration system wherein liquid refrigerant is-delivered directly from the con- 5 denser to the evaporator.

With the evaporator operating at a low temperature and pressure and the condenser at a high temperature and pressure, there is an appreciable entropy loss in cooling the liquid refrigerant to the evaporating temperature.

It is an object of the present invention to lessen the entropy loss in a refrigeration system or to obtain greater efiiciency of operation by utilizing heat energy in the liquid refrigerant which'would otherwise be unexpended or lost.

A further object of the invention is to provide a new and improved process of and apparatus for refrigeration capable of more efliciently" maintaining separate compartments refrigerated- S0, at different temperature levels.

Other objects and advantages will become ap- 4 parent upon an analysis of the system in view of the following description and the exemplary embodiment of the invention shown in the drawing,

SI wherein the single figure diagrammatically illustrates one application of the invention.

Referring to the drawing a compressor I0 supplies compressed refrigerant to a condenser H,

from which it passes to a receiver I2. A cab- 80 inet I3 is divided into compartments C, C-l and G-2 containing, respectively, evaporating units E-l, E-2 and E3 from which gaseous refrigerant is returned to the compressor l0 through suction line I4. The evaporating units are sup- 3 plied with refrigerant successively, thesupply to A the first evaporating unit E--l, being controlled by afloat valve IS in receiver l2 which maintains the liquid refrigerant in said receiver at a predetermined constant level; the supply to the sec- 40 0nd unit E-2 by a similarly operating float valve IS in unit E-l, and the supply to unit E-3 by fioat valve I! in- 15-2. Vaporized refrigerant passes off from the respective evaporating units through'conduits orpipes l8, l9 and 20 into the 46 suction-line H, which is common to said pipes.

Aspirators A! and A-2 having suitable ex- Danding or'ejector nozzles 2i and 22 are provided for stepping up the velocity of the gases passing into the suction line from the respective evap- 50 crating units.

The system operates as follows:

Liquid refrigerant from the condenser ll accumulates in receiver I2, float control valve I5 maintaining the liquid in the receiver at a'pre- 66 determined constant level. From the receiver l2, the liquid refrigerant is delivered into the first evaporating unit E-I wherein it is maintained at a relatively low pressure by the action of the compressor III. In E--l the liquid heat content ofthe refrigerant vaporizes some of the 5 liquid, and this vapor fiows out through expanding nozzle 2| in aspirator Al. The fioat control valve IS in the evaporator E'i is adjusted to maintain the liquid in said evaporator at a predetermined level, and as the supply of liquid 10 is greater than can be vaporized at this stage, the excess liquid is precooled by evaporation and the precooled liquid delivered into the second evaporator stage or unit E2. The compartment 0-! in which the unit E-.2 is located may be, for example, the food compartment of a refrigerator, and the liquid refrigerant in evaporator E2 absorbs heat from the medium or article to be cooled and the vaporized refrigerant is delivered to the suction side of aspirator Al, where additional energy is imparted to the refrigerant vapor by the high velocity vapor leaving the expanding nozzle 2|. Thus the pressure of the vapor leaving the aspirator AI is higher tharzi the pressure of the vapor in the evaporator Similarly, surplus liquid may be delivered from evaporator E- -2 to 13-3, where additional heat is absorbed by the liquid refrigerant and the vapor therefrom delivered to the suction side of aspirator A-2, where additional energy is imparted to the vapor in the suction line It by expanding nozzle 22, so that the pressure'in the latter line is higher than the pressure inevaporator E-3. The compartment C-2 in which evaporator 13-3 is loated may be a furtherseparate refrigerating compartment wherein the temperature is maintained at a lower or different temperature level than that in compartment With a system of this type heat energy which would otherwise be unexpended is rendered available to perform work on the vapor flowing in the suction line or low pressure side of. the system and deliver it to the compressor at a higher pressure than would otherwise be possible. Coincident with .this advantage, is that of maintaining separate compartments to be refrigerated at different temperature levels. 5

' It will-be obvious to those skilled in the art that certain changes may be made in the system without departing from the spirit of the .invention and therefore the invention is not limited to the illustrative embodiment shown in the draw- .ing anddescribed in the specification but only as indicated in the appended claims.

I claim: 4

1; A refrigeration system including a condensing unit and a plurality of evaporators; said evaporators being connected to said condensing unit so that liquid refrigerant flows from one evaporator to another, liquid level responsive means in one evaporator for controlling flow of liquid therefrom to the next evaporator, and aspirating means for utilizing flow of vapor from one of said evaporators to said condensing unit to Withdraw vapor at a lower pressure from a succeeding evaporator.

2. A refrigeration system including a plurality of evaporators, means for supplying liquid refrigerant to a first evaporator, means for removing refrigerant vapor from said first evaporator to precool the said liquid refrigerant, means for passing said precooled. liquid refrigerant to a second evaporator, and means for utilizing the vapor evolved in said first evaporator for doing work and for aiding in the production of a temperature in said second evaporator lower than in said first evaporator.

3. A method of refrigeration which includes vaporizing refrigerant fluid in a plurality of places, withdrawing vaporous refrigerant fluid from one of said places and utilizing flow of withdrawn vapor to withdrawv vapor from a succeeding place at lower pressure, and conducting liquid refrigerant to said first place and then from said first place to said second place so that the liquid refrigerant is precooled in said first place before entering the lower temperature second place and the vapor formed by the precooling utilized to do work.

.ROBERT S. TAYLOR. 

